This sets up the dangerous proposition that D&D the RPG can be declared "not D&D the RPG" by anyone other than the company publishing D&D the RPG.Imho DnD is a Class based fantasy game and if Classes ever disappear then it wont be DnD anymore - of course those classes are just Fighter, Mage, Skill monkey, but those are the pillars.
XP is meaningless, ability scores can be reduced to a single Proficiency bonus and Race has already become a stack of feats. But if Classes ever become a mere feat tree then we may as well play Gurps
We went through this back with 4E and it wasn't a good time.